Fluorescent luminaire



July 2, 1963 D. w. HARLlNG 3,096,028

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D nald 2a Wa United States Patent 3,996,028 FLUREENT LUl /ihJAllRE Donald W. Her-ling, South Milwaukee, Wis, assignor to McGraw-Edison Company, Milwaukee, Wis, a corporation of Delaware Qriginal application Sept. 23, 1957, Ser. No. 685,439. Di-

vided and this application Dec. 29, 1958, Bar. No.

8 -Clainis. (1. 24tl25) This invention relates to fluorescent type luminaires and more particularly to fluorescent luminaires for street lighting and the like. This application constitutes a divisional application carved out of our co-pending application, Serial No. 685,439, filed September 23, 1957 which matured into Patent No. 2,886,699, dated May 12, 1959 and entitled Fluorescent Luminaire.

Fluorescent luminaires utilized for lighting highways are generally mounted on a pole and at a considerable distance above the ground. In both installation and maintenance, the lineman is working from a ladder or the like and, hence, ease of original installation, and ease of access to and handling of all parts of the fluorescent luminaire during maintenance is particularly important.

it is an object of this invention to provide a fluorescent luminaire which is particularly well adapted for easy installation to pole mounted supporting means by one man standing in an elevated position on a ladder or the like.

It is another object of this invention to provide a novel method of installation of a fluorescent luminaire wherein the parts may be individually mounted as separate components, thus, fiording easy installation because of the relatively lighter weight of the individual components as compared to the total weight of the luminaire.

It is a further object of this invention to provide a novel method of mounting a fluorescent luminaire having outer housing means to a pole support comprising, mounting a portion of the housing upon the support means in an inverted position relative to its normal operating position upon the support means, then installing several of the components upon the housing portion prior to rotating the housing to its normal operating position, thus, the inverted housing affords a convenient easy place to rest tools and the like as well as allowing a workman to be working on top of rather than underneath the luminaire housing while installing the other components and making electrical connections, etc.

It is another object of this invention to provide a fluoresc'ent luminaire having a separate component comprising unitary reflector assembly including junction block terminals, lamp holders, lamps, reflecting surfaces all of which may be quickly and easily attachably and detachably mounted as a unit relative to the rest of the luminaire when mounted on a pole in an elevated position.

Another object of the invention is to provide a luminaire as above set forth wherein the unitary reflector assembly is hingedly mounted relative to the rest of the luminaire such that the entire subassembly may be pivotally swung away therefrom to provide access to electrical connections, ballast, mounting means, etc., without necessitating the removal of lamps from the lamp holder thereby reducing breakage of lamps and disturbance of the factory set optical relationships of lamp holders to reflecting surfaces.

It is a further object of the invention to provide a luminaire assembly wherein the electrical circuits may be conveniently checked without necessitating removal of the lamps from the reflector assembly.

A further object of the invention is to provide a luminaire as set forth above wherein the reflector assem- "ice 2 bly is latched into position by a manually operable spring loaded latch means that aflords quick easy access without the use of tools.

A further object of the invention is to provide in a device of the type aforementioned, quick attachable and detachable electrical junction block means mounted on the reflector subassembly which afiords both speedy and easy initial Wiring as well as repair work all of which may be done without tools.

A further object of this invention is to provide a reflector assembly as above described having a particular spacial relationship of lamps which provides an even light pattern with a minimum of glare.

It is a further object of this invention to provide a luminaire as above described having spaced back-to-back parabolic reflecting surfaces which are connected by an intermediate surface portion, said intermediate connecting surface portion being of a configuration adapted to concentrate radiant energy from lamps spaced therebelow in a manner to heat up said lamps to thereby increase the operational efliciency of the lamps when exposed to very cold temperatures and simultaneously eliminate hot spots of light below the luminaire.

Another object of the invention is to provide a luminaire for street lighting and the like which is shallow in height as respect to width, said relationship tending to keep the wind loading of the luminaire at a minimum to reduce the size of support structure for the luminaire.

It is a further object of this invention to provide a reflector assembly as above described which divides the outer casing of the luminaire into upper and lower chambers, said reflector assembly being adapted to prevent radiant heat from the lamp sources from impinging upon the ballasts located in the upper chambers to thereby not increase the temperature surrounding the said ballasts.

Another object of the present invention is to provide a luminaire as outlined above that is well adapted for mass manufacture, is easy to assemble and maintain, is pleasing in apperance, has a long field life and is otherwise weil adapted for the purposes for which it was designed.

The novel features that are characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional objects and advantages thereof will best be understood by the following description of specific embodiments when read in connection with accompanying drawings in which:

PEG. 1 is a side view of a fluorescent luminaire for street lighting purposes mounted in its normal operative position relative to a pole by suitable mounting means, a portion of said view being in section;

FIG. 2 is a vertical sectional view taken along line 2-2 of FIG. -1, the mounting pipe being omitted;

FIG. 3 is a top plan view of the reflector assembly with the lamps removed therefrom, a portion of the electrical circuitry being shown in semi-diagrammatioal form;

FIG. 4 is a so called reflection diagram of the optical characteristics of the reflector assembly shown in FIGS. 1-3, inclusive;

FIG. 5 is a pictorial representation of the vertical and horizontal light patterns provided by a luminaire of the type shown in FiGS. 1-4, inclusive;

FIG. 6 is a semi-diagrammatic view similar to FIG. 4 showing a reflection diagram for an alternative embodiment of reflector configuration;

FIG. 7 is a view similar to FIGS. 4 and 6 showing a re flection diagram for another alternative embodiment of reflector assembly;

FIG. 8 is a view similar to FIGS. 5, 6 and 7 showing a reflection diagram of an alternative spacial relationship 3 of lamps to each other as well as to reflector, and in addition showing an alternative configuration of reflector surfaces;

FIG. 9 is a fragmentary perspective view of a portion of the junction block assembly which is mounted on the reflector assembly, said view showing the quick attachable and detachable electric connection means;

FIG. 10 is a bottom plan view of the upper housing shown in FIGS. 1 and 2, the reflector assembly, electrical components and globe assembly being removed;

FIG. 11 is a fragmentary sectional view showing a collar assembly which coacts with the support means; FIG. 12 is a perspective view showing the upper housing mounted in an inverted position as compared to its normal operating position prior to assemblying the other components thereto in the initial installation of the luminaire.

Before giving a detailed description of the precise configuration and cooperation of the components of the fluorescent luminaire, a short enumeration of the major components and the novel method of their field assembly shall be described. 7

' The major components of the luminaire are the upper outerhousing means 14, the detachable globe assembly means 15, the unitary reflector assembly 16 and electrical control means 19. The total weight of all the aforementioned components is relatively large and the complete assembly is rather bulky. However, individually the components may be readily handled by one man.

In order to provide an easy, one man field assembly of the luminaire in an elevated position, a support means 12 is first positioned upon a suitable pole 11 at a predetermined elevated height such as 30 feet or the like above the street level. The support means 12 is generally fixed at a predetermined angle generally transverse of the street that is to be lighted. As perhaps best shown in FIGS. 1, l and 12, the support means 12 has an elongated portion 12a which may take the form of a pipe or the like and a secondary depending supporting portion 12b. The

electric input leads for the luminaire are preferably brought in through the interior of the support means 12. In order to assemble the components in the field, the housing means 14 is formed with an aperture at one end, said aperture being adapted to receivethe elongated portion 12a of the support means. The housing means 14 is preliminarily mounted in the up side down position shown in FIG. 12. A collar 200 which is fixed to the housing means 14 adjacent the aperture in the housing provides a good suitable bearing for the pipe support 12a at the housing wall. The end of the pipe support 12a is adapted to be positioned in a suitable connecting and leveling means 20 as shown in FIGS. and '12. The level-ing and connecting means 26 is fixedly attached to the housing means 14 in a manner to be later described. After the housing is mounted in the aforesaid up side down position, the electric input wires '13 are suitably attached to an electrical junction box assembly (not shown). The electric control means or ballasts 19 are then fixedly mounted in the housing while the latter is in the aforementioned inverted position and the electrical connections thereto are then made. 7

.The next step in the field assembly is to hin-gedly attach the unitary reflector means to the housing means .also while the latter is in the inverted position. The precise method of attachment shall be more fully explained hereinafter. The necessary electrical connections to the reflector assembly '16 are then made. The housing means 14 is then rotated on the elongated support portion 12a and the leveling of the luminaire then takes place.

The luminaire is preferably first leveled in a transverse direction, the set screw d of the collar 20a and 2e of the leveling and connecting means 20 both being tightened;

after the transverse leveling to fix the luminaire tightly to the support 12a.

Next the end "collar 29b of the leveling means 20 is adjusted relative to a fixed plate 20c and the bolts 20 'wind loading.

are tightened to thus provide longitudinal leveling of the luminaire.

The lamps 35 may then be installed in the reflector assembly 15. It is apparent that the lamps could also be installed simultaneously with the reflector assembly. The final step in the field assembly is to mount the outside (globe assembly 15 upon the housing means 14. The reason for waiting until last on the installation of the lamps and the globe assembly is to reduce the chance of breakage. However, it is to be noted that the globe assembly also can be easily mounted to the housing means '14 prior to the revolving or rotation of the latter if desired. It will also be noted that all of the mounting of the component parts except for the aforementioned lamps and globes, as well as all of the electrical connections, may be performed while working on top of rather than below the component parts. This, of course, is important to an installation man who is working 30 feet or so in the air because if any parts should be dropped they would fall into the housing as versus falling clear to the ground. Further, it is always easier to work on top of rather than beneath the work pieces.

Inasmuch as high output fluorescent lamp tubes are by nature greatly elongated, the luminaire tends to become quite bulky. Great care should be taken to keep the over-all luminaire as shallow as possible to reduce It should be pointed out that the casing for the luminaire 10 is relatively shallow in vertical height (represented by the dimension B) as compared with the Width of the luminaire (represented by the dimension A). This relationship of height to width is most desirable for reduction in wind resistance. It is further noted that the outer configuration of the housing and globe assembly as seen in cross section, FIG. 2, has a somewhat streamlined effect as to further reduce the Wind loading upon the support means 12.

Turning now to a more precise description of the parts. The luminaire 10 in its final assembly, has an outer hollow casing which protects the internal portions from the weather. Broadly, the casing comprises two main parts -as aforementioned, the upper housing means 14 and the detachable, globe assembly 15. Intermediate these two casing parts is a unitary reflector assembly 16 which substantially divides the interior of the elongated hollow easing into two chambers, the upper internal chamber. '17 and the lower internal chamber 18. As is apparent, most of the electrical components and the adjustable connections of the luminaire to the support means are disposed in the upper chamber 17 while the lamps and the reflecting surfaces are disposed in the lower chamber, 18.

The upper housing means 14 comprises a housing member 14a which is preferably made from a single piece of aluminum which is formed intoa substantially shallow inverted elongated cup shaped roof which is adapted to cover and weather proof the working parts of the luminaire. The perspective view, FIG. :12, shows the housing means 14 approximately out of normal operating position. The housing means 14 is preferredly made relatively thin for good heat dissipation purposes. To strengthen the thin housing, supporting ribs 21, which may be formed of square extruded aluminum, may be spacedly disposed transversely to the long dimensionof the housing. The ribs 21 are formed in a manner to fit the inside of the housing as shown.

As shown in FIGS. 10 and 12, the left end of the housing means 14 is formed with an aperture, there being a collar 20a surroundingly mounted to the aperture and suitably fixed to the housing. A set screw 20d is positioned on the collar for easy access from the open end of the housing means 14.

Fixedly attached to the left hand rib, as viewed in FIG. 10, is a downwardly projecting (from operating position of luminaire) plate 20c which is formed with a pair of parallel slots 20k and Zbp. An end collar 20b is formed with threaded apertures spaced the distance of the slots 20p and 20k. A pair of suitable bolts 26 are disposed in said slots and in said aperulres for adjustment of the end collar 29b relative to the fixed plate 200 to longitudinally level the luminaire. To keep out bugs, moisture, etc. sealing means 29] such as neoprene, etc., may be disposed in the end collar 2617, the sealing means 20 being suitably pierced to allow the electrical input condoctors 13 to extend therethrough as shown in FIG. 2.

Electric control means 19, known in the art as ballasts, are fixedly disposed within the upper chamber 17. It is to be noted that the ballasts are preferredly fixedly mounted by suitable fastening means such as bolts 19a against the inner surface of the member 14a for heat dissipation purposes. The function of the ballasts and the electrical connections thereto from the power source connectors 13 are Well known and therefore are not shown and will not be discussed further.

Near the open edges and along the long sides of the interior of the housing member 14a, are a pair of elongated L-shaped strips of metal 22, one portion of member 22 firmly attached to the housing 14:: and the other portion 22a extending inwardly as shown in FIGS. 2, 10 and 12. The members 22 are disposed on opposite sides of the housing means such that the inwardly extending portions 22:: face each other as best shown in FIG. 2. Fixedly attached to zone of the inwardly extending portions 22a are a plurality of latch tab members 23 which may be suitably and spacedly attached by a screw, bolt or the like as shown on the left hand side of FIGS. 2 and 10. The latch means 25 which is mounted upon the tabs 23 will be described later. Substantially opposite from the tab members 23 on the opposite inwardly extending portion 22a, i.e., on the right side as viewed in FIG. 2, are a plurality of spaced hinge tabs 24 which are configured in a manner to receive a detachable hinge member 34- as shall be more thoroughly described hereafter.

Turning now to the detachable globe assembly 115 and the sealing means therefor, it is to be pointed out that the globe assembly 15 is hingedly mounted in place relative to the housing means 14 by suitable combination latch and hinge means 49. The precise configuration f the latch and hinge means and the sealing means surrounding the globe means 15 are more particularly described in a :copending application of Donald W. Harling and Philip B. Clark filed the 23rd day of September, 1957, and having Serial No. 685,439 and assigned to the same assignee as the present invention. For purposes of this disclosure, suflice it to say that the globe assembly comprises a one piece elongated cup shape plastic globe member which is detachably hingedly mounted to both sides of the upper luminaire housing 14a such that it may be swung open from either side for access to the interior of the luminaire it} as shown in dotted lines in the far right hand side of FIG. 2.

Once the globe assembly is hingedly or completely detached relative to the hous ng, access is had to the reflector assembly 16. The reflector assembly 15 is a unitary assembly in that it may be readily attached and detached from the housing member 1411 as a separate subassembly as well as hingedly swung to an open position for access to the upper chamber 17. The main components of assembly 16 are the lamp holder means 29, elongated fluorescent type lamps 35, quick attachable and detachable electric junction block means 30, parabolic reflecting means 31 and strengthening rib means 32.

Turning now to the separate components, the parabolic reflector means 31 may be formed out of a single piece of aluminum, the bottom surface being highly polished, and configured such that a pair of spaced back-to-back parabolic reflecting surfaces 310 and 3111 are formed to direct light from the light sources disposed at the focal point thereof laterally outwardly of the luminaire in opposite preferred directions. The surfaces 31a and 3117 are connected by an intermediate surface 310 all of which will be more particularly described in explanation of the reflection diagram.

As perhaps best shown in FIGS. 2 and 3, reflector means 31 may be fixed to and depend from transverse strengthening ribs .32. Any number of types of fastening means of the ribs 32 to the reflector 31 may be used, one such being screws 33. The rib means 32 are generally U-shaped in configuration and the side walls of the left end of the rib as viewed in FIG. 3 are preferably formed at 32!) with suitable apertures to receive a cotter pin 34 which serves as a hinge. As shown, any number of ribs 32. and hinges 3- 2 may be spaced along the top side of the reflector assembly 16. All of the cotter pins 34 coact with the rib apertures 32b and with the hinge tabs 24 spaced along the open end of the housing means 14 to serve as a convenient quick detachable hinge. t is, thus, apparent that the whole assembly 16 may be rotated on the hinge 24, and if desired, the hinges themselves may be removed so as to take the entire reflector assembly 16 out of the housing 1 2- so that it may be worked upon on the ground and/or for substitution of a new assembly if that is desired. As aforementioned, the original field installation is exceedingly simple, merely requiring insertion of the hinge 34 in proper places while the housing is in the inverted position shown in FIG. 12.

The base portion of the right hand end of the ribs 32 as viewed in FIG. 3 may be formed with a pair of slots which are disposed in right angle relationship to each other. The long slot 32:: runs along the long dimension of the ribs 32 and the shorter slot 32c is generally transverse to the rib. The slots 32a and 320 are designed to cooperate with the spring loaded manually operable latch means 25 which is attached to latch tab 23.

The latch means 25 is operable to selectively engage and hold the reflector assembly id in operative position within the casing when the other end of the ribs 32 are hingedly attached by the cotter pin 34. The latch means 25 comprises a latch member having an enlarged ring type head portion 26, an elongated portion extending through the latch tab 23, a suitable coil spring 27 surroundingly mounted to the elongated portion, and a spring retaining collar 28. The head portion of the latch 25 is larger than the rib slot 32c and smaller than slot 32a; The alternative positions of the head portion of the latch means relative to the rib slots 32a and 320 is shown in dot and dash lines in FIG. 2. It will be apparent that an operator may pull the latch head portion 26 downwardly as viewed in FIG. 2 to rotate the latter so that it will cooperate with the respective desired slots formed in the rib to alternatively latch or unl-atch one side of hinge reflector assembly 16 to the housing means -14.

Suitable lamp holder means 2% and 2% may be fixedly mounted to each end of the reflector assembly 1% for movement therewith. More particularly lamp holder means 29a, as shown at the bottom of FIG. 3, has a first upper portion 291 and a depending portion 290. The portion 2% extends for attachment to the rib means 32 by the fastening means 33 and the depending portion 290 is adapted to mount lamp receiving bases 29d. In the particular embodiment described, four lamp bases 29d are disclosed in horizontal alignment and mounted on the depending portion 290 of the lamp holder means.

On the other end of the reflector assembly 16 is the lamp holder means 2% having a first mounting portion 29g and a depending portion 29h. The depending portion 2% has corresponding lamp receiving base members 29k mounted in opposed relation to the lamp holders 29d in the usual manner. The lamp holder bases 29k has a spring loaded portion 29k which aids in mounting the lamps 35' in the bases 25% and 29d. It is to be noted that the lamp bases 2% and 29k are positioned below the reflector surfaces 31a, 31c and 31b so that a portion of the reflector surfaces is within one inch of the outer surface of each lamp when the lamps are installed in the 7 bases. This is required for good starting of the fluores cent type tubes 35. V As best shown in FIG. 3, quick attachable and detachable junction block means 39a and 301) are fixedly mounted on lamp holder portions 23 and 29g, respectively. The junction blocks represent a plurality of electrical connectors and insulator blocks which are connected to the respective lamp bases in a manner well understood in the art. Most of the electrical connections of the junction blocks to the lamp bases 29a and 2912 as well as from the ballasts 19 to the blocks 3% and 30b have been omitted, one circuit only being shown in semidiagrammatic form.

The perspective view, FIG. 9, shows a frictional type of quick attachable and detachable type of electrical connection that is preferred and which requires no tools in making the connection between the male 30d and female 300 members. The ease of making electrical connections between the ballasts 19 and the lamps 35 is particularly important when it is considered that the man assembling the luminaire in the field is standing considerable distance above the ground on a ladder or the like, and, hence, the ease of attachment and disattachment becomes particularly important both in original installation and repair.

Returning now to the particular configuration of reflector 31 and the relative positional relationship of the lamps 35 relative to the reflector 31 and to each other. It will be noted that the reflector means 31, as shown in FIG. 4 is so configured as to form opposed back-to-back reflector parabolic surfaces 31a and 31b. Each surface 31a and 31b sends reflected light in a preferred direction.

as shown by arrows 36 and 37 from lamps 35a and 35d, respectively, disposed at the focal points of the parabolas. The reflected light from surfaces 31a and 31b is, thus,

' reflected outwardly in a lateral direction to throw light generally transversely of the luminaire to light the street.

The parabolic surfaces 31a and 31b are connected by an intermediate connecting portion 31c which serves as a heat trap and reduces light hot spots below the luminaire. It is to be particularly noted that the connecting resents a light ray directed toward the reflecting surface 31c which returns to source 3512, then is directed oflf in greatly reduced intensity as shown by dotted arrow 40a.

' The intensity of the light ray 44 is reduced approximately 15 percent each time it impinges upon a reflecting surface. This energy is lost in the form of heat. The same relationship of reflected light is true of the other center light source 350. It also'is to be noted that no 'baflles are interposed between the four lamps 35a to 35d, inelusive and, hence, a certain amount of direct light is impinging upon the adjacent light sources. As afore mentioned, the reason for the configuration of the center interconnecting surface 31c is twofold, one, it eliminates excessive hot spots of light immediately below the luminaire and, also, aids in tending to heat up the lamps for good cold weather operation. While. there is a disadvantage to Warm weather operation due to this extra heating elfect of the reflected light, the disadvantage is more than compensated for by the great increase in efficiency during cold weather operation.

It will be noted that the lamps 350: through 35d are in horizontal alignment and spaced such that a line from the center of each of the individual sources and tangential to the next adjacent source forms a direct light cutoff .plane that is parallel to the preferred directions established by the parabolic surfaces 31:: and 31b, respectively. More particularly a line drawn from the center of lamp 35a tangential to lamp 35b establishes a plane 41 which is substantially parallel to arrow 37 which represents the preferred direction established by reflecting surface 3Lb. It will be noted that the cutoff planes established by lamps 35b and 350 relative to lamps 35c and 35d, respectively, which form planes 42 and 43' are simi lar and substantially parallel to the plane established by line 41. Conversely, lamp 35d has a cutoff plane 40 established by lamp 350 which is parallel to the plane represented by lines 36 which are in the preferred direction established by the parabolic reflecting surface 31m. The same holds true for the cutoff planes represented by lines 38 and 39 which are established by lamps 35a and 35b relative to lamp 35b and 35c, respectively. It will be apparent that this particular relationship of lamps to the lamps to each other and the relationship to the reflector surfaces tend to make a luminaire which gives a very fine light pattern with minimum of glare as shown by the candle power distribution curve diagrams shown in FIG. 5. a V

More particularly the lateral distribution 46and vertical distribution 45 are illustrative candle power curves of a 6-foot luminaire, curve 46 being taken at 60? through vertical at an ambient temperature of 24 centigrade in still air with four cool white, fluorescent light tubesand curve 45 is a vertical distribution through 90 lateral taken under the same conditions as curve 46..

FIGS. 6-8, inclusive, show alternative reflection diagrams and reflector configurations as well as arrangements of lamps to reflector and each other all offlwhich produce substantially the same results as set forth with reflector 31 just described. Similar parts have been marked with similar numbers but have been prefixed with different numbers to differentiate the particular figure involved, i.e., reflecting surface 31a of FIG. 4 is denominated 131a in FIG. 6, 231:: in FIG. 7 and 331a in FIG. 8,

and other similar parts are likewise denominated with clusive, as reflector portion 310 of FIG. 4 in that portion 1310 will tend to reflect a large portion of the light back toward the various lamp sources in a manner to heat up same and to prevent a deleterious concentration of light immediately below the luminaire.

FIG. 7 shows a reflector configuration wherein the parabolic reflecting surfaces 231a and 2251b extend downwardly to the cutoff planes as represented by .the arrows,

the planes represented by arrows 238 and 241 establishing the furthest downward limit that reflector surface 231a may extend and the planes established by arrows .240 and 243 establish the furthest downward limit reflector surface 2351b may extend. The intermediate connecting surfaces 2310 and 231d as shown are generally circular in shape and are designed to trap a good'deal of the light in that they reflect the light directly back into the light sources 23517 and 235a for-reasons aforestated.

FIG. 8 shows a slightly diiferent configuration from the foregoing in that the lamps 335b and 3350 are raised slightly above the horizontal alignment of lamps 335a and 335d. The two outer lamps, namely 335a and 335d, are still disposed at the focal points of the parabolic surfaces 331a and 331b, respectively; however, the cutoff plane between lamps 3 35b and 335a extends in the pre-' ferred direction 336 and the cutoff plane between lamps tion 337. One difference in the reflector 31'shown in 9 FIG. 8 is that the cutoif planes established by the two outer lamps relative to the two inner lamps are not in the preferred direction.

From the foregoing description it will be apparent that the luminaire hereinbefore described and the alternative embodiments thereof are particularly well adapted for providing good, eflicient street lighting while being exceedingly easy to operate and maintain.

Although specific embodiments have been shown and described, it is with full awareness that many modifications thereof are possible. The invention, therefore, is not to be restricted except insofar as is necessitated by the prior art and by the spirit of the appended claims.

What is claimed as the invention is:

1. In a fluorescent luminaire, reflector means comprising at least two spaced oppositely disposed parabolic re flecting surface means each operable to direct light from light sources disposed at their focal points in a preferred direction and connecting surface means interposed between and connecting said spaced parabolic reflecting surface means, and lamp means comprising a plurality of elongated horizontally aligned light sources disposed below said reflector means, at least one of said light sources positioned at the focal point of each parabolic reflecting surface means and cooperating therewith and another of said light sources positioned adjacent to and cooperating with said connecting surface means, said connecting surface means being of a configuration and said light sources being arranged relative to each other and said connecting surface means that said connecting surface means intercepts a substantial portion of the light from said another light source and directs said intercepted light into each of said light sources to thereby convert said light into heat and reduce the concentration of light immediately below the luminaire.

2. In a fluorescent luminaire, reflector means comprising at least two spaced parabolic reflecting surface means each operable to direct light from a light source disposed at its focal point in a preferred direction and connecting surface means interposed between and connecting said spaced parabolic reflecting surface means, and lamp means comprising a plurality of elongated aligned light sources, at least one of said light sources positioned adjacent to and cooperating with each parabolic reflecting surface means and another of said light sources positioned adjacent to and cooperating with said connecting surface means, said connecting surface means being of a configuration and said light sources being arranged relative to each other and said connecting surface means that said connecting surface means intercepts a substantial portion of the light from said another light source and directs said intercepted light into each of said light sources to thereby convert said light into heat and reduce the concentration of light immediately below the luminaire.

3. In a fluorescent luminaire, reflector means compris ing at least two spaced oppositely disposed parabolic reflecting surface means each operable to direct light from a light source disposed at its focal point in a preferred direction and connecting surface means interposed between and connecting said spaced parabolic reflecting surface means, and a plurality of elongated light sources disposed below said reflector means, at least one of said light sources positioned at the focal point of each parabolic reflecting surface means and cooperating therewith and a pair of said plurality of light sources positioned adjacent to and cooperating with said connecting surface means, said connecting surface means being of a configuration and said light sources being arranged relative to each other and said connecting surface means that said connecting surface means intercepts a substantial portion of the light from said pair of light sources and directs said intercepted light into said light sources to thereby convert said light to heat and reduce the concentration of light immediately below the luminaire.

4. In a fluorescent luminaire, reflector means comprising at least two spaced oppositely disposed parabolic reflecting surface means each operable to direct parallel rays of light from a light source disposed at its focal point in a preferred direction and connecting surface means interposed between and connecting said spaced parabolic reflecting surface means, and a plurality of elongated light sources disposed below said reflector means, at least one of said light sources positioned at the focal point of each parabolic reflecting surface means and cooperating therewith and a pair of said plurality of light sources positioned adjacent to and cooperating with said connecting surface means, said connecting surface means being of a configuration and said light sources being arranged relative to each other and said connecting surface means that said connecting surface means intercepts a substantial portion of the light from said pair of light sources and directs said intercepted light into each of said light sources to thereby convert said light into heat and reduce the concentration of light immediately below the luminaire, each of said light sources being positioned tangent to a line extending from the center of the next adjacent light source and parallel to said light rays in one of said preferred directions whereby said light sources establish cutoff planes parallel to said light rays in said preferred directions.

5. In a fluorescent luminaire, reflector means comprising at least two spaced oppositely disposed parabolic reflecting surface means each operable to direct parallel rays of light from a light source disposed at its focal point in a preferred direction and connecting surface means interposed between and connecting said spaced parabolic reflecting surface means, and a plurality of elongated light sources disposed below said reflector means, at least one of said light sources positioned at the focal point of each parabolic reflecting surface means and cooperating therewith and a pair of said plurality of light sources positioned adjacent to and cooperating with said connecting surface means, each of said light sources disposed at the focal points of said parabolic reflecting surface means being positioned tangent to a line extending from the center of respective ones of said pair of light sources and parallel to said light rays in one of said preferred directions whereby cutoff planes are established for said pair of light sources parallel to said light rays in said preferred directions.

6. In a fluorescent luminaire, reflector means comprising at least two spaced oppositely disposed parabolic reflecting surface means each operable to direct parallel rays of light from a light source disposed at its focal point in a preferred direction and connecting surface means interposed between and comrecting said spaced parabolic reflecting surface means, and a plurality of elongated light sources disposed below said reflector means, at least one of said light sources positioned at the focal point of each parabolic reflecting surface means and cooperating therewith and a pair of said plurality of light sources positioned adjacent said connecting surface means and cooperating therewith, the axis of each of said elongated light sources being disposed on a single substantially horizontally aligned plane and each of said light sources being positioned tangent to a line extending from the center of next adjacent light source and parallel to said light rays in one of said preferred directions whereby said light sources establish cutofi planes parallel to said light rays in said preferred directions.

7. In a luminaire, reflector means comprising at least two spaced parabolic reflecting surface means each operable to direct light from a light source disposed at its focal point in a preferred direction and connecting surface means interposed between and connecting said spaced parabolic reflecting surface means, and lamp means comprising a plurality of elongated light sources, at least one of said light sources positioned adjacent to and cooperating with each parabolic reflecting surface means and another of said light sources positioned adof the light from said another light source and directs said light into each of said light sources to thereby convert said light into heat and reduce the concentration of light immediately below the luminaire.

8. In a luminaire, reflector means comprising at least two spaced oppositely disposed curvilinear reflecting surface means' and connecting surface means interposed between and connecting said spaced curvilinear reflecting surface means, and a plurality of elongated light sources disposed adjacent said reflector means, at least one of said light sources positioned at the focal point of each of said curvilinear reflecting surface means so that each of said curvilinear reflecting surface means directs parallel rays of light in a preferred direction and at least one of said light sources positioned adjacent said connecting surface means and cooperating therewith, each of said elongated light sources being positioned tangent to a line extending from the center of the next adjacent light source and parallel to said light rays in one of said preferred direc tions so that said light sources establish cutoff planes parallel to said light rays in said preferred directions.

References Cited in the file of this patent UNITED STATES PATENTS 1,464,166 Benjamin Aug. 7, 1923 2,293,672 Bookman Aug. 18, 1942 2,617,013 Smyth NOV. 4, 1952 2,755,374 Ott et a1. July 17, 1956 2,875,323 Harling Feb. 24, 1959 

7. IN A LUMINAIRE, REFLECTOR MEANS COMPRISING AT LEAST TWO SPACED PARABOLIC REFLECTING SURFACE MENS EACH OPERABLE TO DIRECT LIGHT FROM A LIGHT SOURCE DISPOSED AT ITS FOCAL POINT IN A PREFERRED DIRECTION AND CONNECTING SURFACE MEANS INTERPOSED BETWEEN AND CONNECTING SAID SPACED PARABOLIC REFLECTING SURFACE MEANS, AND LAMP MEANS COMPRISING A PLURALITY OF ELONGATED LIGHT SOURCES, AT LEAST ONE OF SAID LIGHT SOURCES POSITIONED ADJACENT TO AND COOPERATING WITH EACH PARABOLIC REFLECTING SURFACE MEANS AND ANOTHER OF SAID LIGHT SOURCES POSITIONED ADADJACENT TO AND COOPERATING WITH SAID CONNECTING SURFACE MEANS, SAID CONNECTING SURFACE MEANS BEING OF A CONFIGURATION AND SAID LIGHT SOURCES BEING POSITIONED RELATIVE TO EACH OTHER AND SAID CONNECTING SURFACE MEAN THAT SAID CONNECTING SURFACE MEANS INTERCEPTS A SUBSTANTIAL PORTION OF THE LIGHT FROM SAID ANOTHER LIGHT SOURCE AND DIRECTS SAID LIGHT INTO EACH OF SAID LIGHT SOURCES TO THEREBY CONVERT SAID LIGHT INTO HEAT AND REDUCE THE CONCENTRATION OF LIGHT IMMEDIATELY BELOW THE LUMINAIRE. 